Male athletes have been reported to improve VO2max and time to exhaustion after consuming a fat-rich diet. Highly trained male triathletes (N = 5) consumed normal, fat-rich, and carbohydrate rich diets, each for seven days before performing a cycle ergometer test.

There were no differences in ratings of perceived exertion between trials. The fat-rich diet did not improve VO2max, time to exhaustion, or substrate utilization over the carbohydrate-rich diet effects.